The present invention relates to a containment or oil boom for preventing containment of oil which is spilled to sea.
When an oil spill accident occurs at sea, a containment boom is used to surround the oil spill, in order to prevent containment of the oil spill. Each of conventional containment booms has a structure in which a plurality of cylindrical floats are connected to one another, as disclosed in each of Patent literatures 1 to 5. In each of Patent literatures 1 to 5, a seat body or a bag body and a plummet body hang from each of the cylindrical floats into sea to prevent the oil from passing through the lower end of each float.
(Patent literature 1)
Japanese Patent Publication Tokkai Hei 11-100833
(Patent literature 2)
Japanese Patent Publication Tokkai Hei 11-43925
(Patent literature 3)
Japanese Patent Publication Tokkai Hei 10-292357
(Patent literature 4)
Japanese Patent Publication Tokkai Hei 10-18273
(Patent literature 5)
Japanese Patent Publication Tokkai Hei 9-151445
However, a gap often occurs between sea level and each of floats in each of conventional containment booms or waves get over the floats, inasmuch as it is difficult for the cylindrical floats to move in synchronization to movements of waves and currents. As a result, oil leaks out of the containment boom. In addition, the seat body becomes deformed or curls up on the basis of violent movements of waves and currents, inasmuch as the seat body is made of a flexible material, although the seat body hangs into sea and is vertically pulled down by the plummet body. As a result, oil leakage occurs in sea.